The high prevalence and incidence of HIV among men who have sex with men (MSM) in New York City requires further understanding of individual and contextual factors underlying unprotected sex, specifically among MSM of color and those in cultural niches that may favor risky sex. Our three-year exploratory study will focus on MSM who meet sexual partners through the Internet to intentionally engage in condomless high-risk sex in situations in which there is risk of HIV transmission. The specific aims of the study are (1) To describe the most popular Internet contexts in which the virtual encounters that lead to condomless sex among NYC's MSM take place. This description will include features of sites, organization, mode of governance, users' characteristics, verbal and non-verbal exchanges, and implicit and explicit rules. (2) To describe intentional condomless sex and its associated self-identity, its attributed meanings, and the psychological correlates (underlying motivations, emotions, and justifications) that precede, are concurrent with, and follow it. (3) To contrast the above-mentioned factors by ethnic group (African American, Latino, Asian Pacific Islander, and European American). (4) To assess the receptiveness of Internet users who engage in these behaviors to HIV-prevention innovations that do not involve condoms, such as rectal microbicides or HIV vaccines. The study will have three main components: (1) an Internet ethnographic exploration focusing on the six more popular Internet sites used by MSM residing in the New York metropolitan area to connect with other MSM with the intention of engaging in condomless sex; (2) in-depth face-to-face interviews of 24 key informants, e.g., webmasters of local Internet sex sites, on-line discussion moderators, and leaders identified by regular users of Internet sex sites; and (3) individual face-to-face assessments of 120 regular users of Internet gay sex sites (30 African American, 30 Latino, 30 Asian Pacific Islander, and 30 European American) recruited through the Internet among those seeking to engage in condomless sex with other men (HIV-negative men who seek to have unprotected receptive sex with new partners they meet over the Internet will be oversampled two to one so that two-thirds of the sample will be HIV-negative). Qualitative and quantitative data analysis will be undertaken by the investigators in consultation with experts at the HIV Center for Clinical and Behavioral Studies, including the Statistics, Epidemiology, and Data Management Core as well as two external consultants with expertise in MSM of color.